Damien Geradin, Dr Anne Layne-Farrar, Nicolas Petit

This chapter describes the leading schools of thought in regards to competition economics as they have evolved over the years. Classical and neoclassical economists were the first to focus on competition issues. The classical economists saw competition as a behavioural process. Meanwhile, with the neoclassical economists came a structural interpretation of competition. Immediately after the Second World War, competition economics became more normative. The chapter then looks at the methodological aspects of competition economics or, more concretely, the instruments and concepts on which competition economics rely. The main focus of study of competition economics is ‘market power’. Indeed, EU competition rules today are based, if not wholly at least mainly, on the concept of market power. Market power can enable behaviours with pernicious effects on economic efficiency. Thus, economists have designed instruments to help authorities, courts, and undertakings to identify and measure market power and its possible abuses.